test: create RetryMiddlewareTest

Author: teandr

tests/Downloader/Middleware/RetryMiddlewareTest.php

@@ -0,0 +1,117 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright (c) 2024 Kai Sassnowski
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ *
+ * @see https://github.com/roach-php/roach
+ */
+
+namespace RoachPHP\Tests\Downloader\Middleware;
+
+use PHPUnit\Framework\TestCase;
+use RoachPHP\Downloader\Middleware\RetryMiddleware;
+use RoachPHP\Scheduling\ArrayRequestScheduler;
+use RoachPHP\Scheduling\Timing\ClockInterface;
+use RoachPHP\Scheduling\Timing\FakeClock;
+use RoachPHP\Testing\Concerns\InteractsWithRequestsAndResponses;
+use RoachPHP\Testing\FakeLogger;
+
+final class RetryMiddlewareTest extends TestCase
+{
+    use InteractsWithRequestsAndResponses;
+
+    private RetryMiddleware $middleware;
+
+    private ArrayRequestScheduler $scheduler;
+
+    private FakeLogger $logger;
+
+    protected function setUp(): void
+    {
+        $this->scheduler = new ArrayRequestScheduler($this->createMock(ClockInterface::class));
+        $this->logger = new FakeLogger();
+        $this->middleware = new RetryMiddleware($this->scheduler, $this->logger);
+    }
+
+    public function testDoesNotRetrySuccessfulResponse(): void
+    {
+        $response = $this->makeResponse(status: 200);
+        $this->middleware->configure([]);
+
+        $result = $this->middleware->handleResponse($response);
+
+        self::assertSame($response, $result);
+        self::assertFalse($result->wasDropped());
+        self::assertCount(0, $this->scheduler->forceNextRequests(10));
+    }
+
+    public function testDoesNotRetryNonRetryableErrorResponse(): void
+    {
+        $response = $this->makeResponse(status: 404);
+        $this->middleware->configure(['retryOnStatus' => [500]]);
+
+        $result = $this->middleware->handleResponse($response);
+
+        self::assertSame($response, $result);
+        self::assertFalse($result->wasDropped());
+        self::assertCount(0, $this->scheduler->forceNextRequests(10));
+    }
+
+    public function testRetriesARetryableResponse(): void
+    {
+        $request = $this->makeRequest('https://example.com');
+        $response = $this->makeResponse(request: $request, status: 503);
+        $this->middleware->configure([
+            'retryOnStatus' => [503],
+            'maxRetries' => 2,
+            'initialDelay' => 500,
+        ]);
+
+        $result = $this->middleware->handleResponse($response);
+
+        self::assertTrue($result->wasDropped());
+
+        $retriedRequests = $this->scheduler->forceNextRequests(10);
+        self::assertCount(1, $retriedRequests);
+
+        $retriedRequest = $retriedRequests[0];
+        self::assertSame(1, $retriedRequest->getMeta('retry_count'));
+        self::assertSame('https://example.com', $retriedRequest->getUri());
+        self::assertSame(500, $retriedRequest->getOptions()['delay']);
+    }
+
+    public function testStopsRetryingAfterMaxRetries(): void
+    {
+        $request = $this->makeRequest()->withMeta('retry_count', 3);
+        $response = $this->makeResponse(request: $request, status: 500);
+        $this->middleware->configure(['maxRetries' => 3]);
+
+        $result = $this->middleware->handleResponse($response);
+
+        self::assertSame($response, $result);
+        self::assertFalse($result->wasDropped());
+        self::assertCount(0, $this->scheduler->forceNextRequests(10));
+    }
+
+    public function testCalculatesExponentialBackoffCorrectly(): void
+    {
+        $request = $this->makeRequest()->withMeta('retry_count', 2);
+        $response = $this->makeResponse(request: $request, status: 500);
+        $this->middleware->configure([
+            'initialDelay' => 1000, // 1s
+            'delayMultiplier' => 2.0,
+        ]);
+
+        $this->middleware->handleResponse($response);
+
+        // initialDelay * (delayMultiplier ^ retry_count)
+        // 1000 * (2.0 ^ 2) = 1000 * 4 = 4000ms
+        $retriedRequest = $this->scheduler->forceNextRequests(10)[0];
+        self::assertSame(4000, $retriedRequest->getOptions()['delay']);
+    }
+}